The present invention relates to transmission control devices for vehicles.
Electronic transmission control devices for automatic transmissions and automated mechanical transmissions, collectively referred to as automated transmissions, are known. Fully automatic transmissions automatically shift between gears, typically using pressurized fluid to engage several drive members together by friction to achieve a selected gear ratio. In automated mechanical transmissions, electronic, hydraulic and/or pneumatic actuation is used to engage and disengage mechanical clutches to achieve a desired gear ratio. In some automated mechanical transmissions, the driver must manually engage the clutch when starting the vehicle from a stopped position or when coming to a stop.
In many modern automated transmissions, a transmission control device is electronically connected to the transmission, and particularly, to a transmission ECU (electronic control unit). When a driver actuates the transmission control device, such as a floor mounted shift lever, the driver's desired action is evaluated by the transmission ECU and then performed if within the range of acceptable actions for the current conditions. For example, a typical transmission control device may allow a driver to (a) select a transmission mode setting (e.g., "Park," "Drive", "Neutral," and "Reverse"); (b) upshift/downshift manually while a particular mode setting is selected (e.g., to upshift/downshift between the various ratios available when the forward "Drive" mode is selected); and/or (c) to disable this manual upshift/downshift functionality. As one example, the driver's attempt to select the Reverse gear setting while the vehicle is moving forward may be prevented by the transmission ECU logic if the speed of the vehicle is above a predetermined limit.
In known automated transmission systems, the electronic transmission control device is typically a floor mounted lever and/or a button. It is common for the lever to be mounted to the floor in the cab of the vehicle, similar to the positioning of a shift lever for a conventional manual transmission. Alternatively, some transmission control devices are mounted to the dashboard of the vehicle. These devices may include one or more push buttons for actuating one or more functions.